The present invention relates generally to absorbent articles intended for personal wear, and more particularly to such absorbent articles having an absorbent composite secured to a stretchable substrate of the article.
Absorbent articles such as diapers, training pants, incontinence garments, feminine hygiene products, etc. conventionally comprise a liquid permeable body-facing liner, a liquid impermeable outer cover, and an absorbent core (also referred to as an absorbent body or absorbent structure) formed separate from the outer cover and liner and disposed therebetween for taking in and retaining liquid (e.g., urine, menses) exuded by the wearer. In some of these absorbent articles, the outer cover and/or the liner are stretchable to permit some expansion of the article when necessary to provide a better fit on the wearer. During use, the article is subjected to forces such as those generated by loading of the absorbent article and movement of the wearer. These forces can cause the absorbent core to shift within the absorbent article, to tear, or to otherwise become permanently distorted, all of which reduce the intended absorbent characteristics of the absorbent core and increase the possibility of liquid body exudates leaking from the article.
To this end, it is known to secure the separately formed absorbent structure to the outer cover and/or the liner, such as using adhesive or by thermal or ultrasonic bonding, to prevent the absorbent core from shifting as the article is stretched and unstretched during usage. However, securing the absorbent core to the outer cover or liner in this manner tends to reduce the stretchability of the substrate to which the absorbent core is secured, thereby reducing the flexibility of the absorbent article. Moreover, while securing the absorbent core to the outer cover and/or liner reduces the risk of shifting and distortion, stretching of the substrate to which the separately formed absorbent core is secured can still result in tearing of the absorbent core.
Also, conventional absorbent cores are typically constructed of superabsorbent material particles and hydrophilic fibers loosely mixed and entangled together to form an absorbent batt. In some absorbent cores, the superabsorbent material is concentrated in certain target areas of the absorbent article where more absorption is needed. When such an absorbent core is disposed between a stretchable outer cover and liner, the superabsorbent particles and hydrophilic fibers shift around as the absorbent article is stretched and unstretched during usage. The displacement of the superabsorbent particles and hydrophilic fibers from the target areas can lead to leakage from the absorbent article and/or, where the superabsorbent particles accumulate in a certain area, swelling of the particles upon absorbing liquid can make wearing the article feel uncomfortable. Such shifting may also lead to a degraded appearance and a perception of poor quality.